The invention relates to a process and an arrangement for producing packages used as feeding packages for twisting, onto which two prestrengthened Yarn components are wound side-by-side as a double yarn, these yarn components, each being drafted and subsequently, in each case, false-twisted, and then guided together and wound onto the spool as a double yarn.
In a process of the initially mentioned type, such as disclosed in German Published Examined Application DE-A 36 06 932, corresponding to U.S. Pat. No. 4,761,946, it is possible that one of the two yarn components may break. It should then be avoided that the remaining yarn component is wound onto the partially wound spool alone, because this may interfere considerably with the subsequent spinning operation. It is therefore provided that, in the case of a breakage of one yarn component, the other yarn component also is cut. This approach may be sufficient for manual spinning, in which the operator searches for the broken yarn end and for the cut yarn end on the partially wound spool and subsequently withdraws the double yarn from the partially wound spool for a piecing operation. Since, as a rule, it must be assumed that the two yarn components do not have the same length, and that therefore the ends of the yarn components are located at different points on the circumference of the partially wound spool, considerable difficulties arise for an automatic piecing arrangement which must then search for and take up two yarn ends.
In order to solve this problem for an automatic piecing arrangement, it was suggested in an older patent application, German application (P 38 05 338.1), corresponding U.S. application Ser. No. 311,731, filed Feb. 17, 1989, which is no prior publication, that, when one yarn component breaks, both yarn components are jointly cut in the area in which they are still both present. As a result, it is achieved that the two ends of both yarn components are located at the same point. It is also suggested that, when one yarn component breaks, the partially wound spool is stopped before the broken end has moved onto the partially wound spool. Both solutions permit an automatic finding and rewithdrawing of the two yarn components from the partially wound spool in order to then carry out a piecing.
An object of this invention is to provide a process and an arrangement of the initially mentioned type, where it is possible, after a breakage of only one yarn component, to find both yarn components also by means of an automatic piecing arrangement and wind them off the partially wound spool for a piecing process.
This object is achieved in that, when one yarn component breaks, the winding-on is interrupted, the unbroken yarn component being gripped and held ready at a given point, after which, for the purpose of piecing, the unbroken yarn component is taken up and wound off the partially wound spool, this unbroken yarn component taking along the broken yarn component.
The invention is based on the recognition that both yarn components break simultaneously only in negligibly few special cases, so that, in these special cases, the piecing can be carried but at least partially by an operator. The interruption of the winding-on prevents that the end of the broken yarn component is rolled into the body of the partially wound spool. The unbroken yarn component is located in a known position so that it can be taken up easily by an automatic piecing device and wound off the partially wound spool. Since a certain connection exists between the two yarn components, and since the end of the broken yarn component is not rolled into the body of the partially wound spool, the broken yarn component, when the unbroken yarn component is wound off, can also be wound off without any difficulty.
In a further development of the invention, it is provided that, when one yarn component breaks, the broken yarn component is connected with the remaining yarn component. This additional connection provides further assurance that the remaining yarn component, during a winding-off, takes along the end of the broken yarn component and also winds off this broken yarn component during a winding-off operation.
In a further development of preferred embodiments of the invention, it is provided that, when one yarn component breaks, the cross-winding is interrupted. As a result, it is ensured that the end of the broken yarn component does not move away from the remaining yarn component as a result of the cross-winding motion.
In a further development of preferred embodiments of the invention, it is provided, in the case of an arrangement for producing packages used as feeding packages for twisting having two yarn components, which are wound up side-by-side, having devices for drafting, having devices for false-twisting, having devices for the guiding-together of the yarn components, and having devices for the winding-up of the guided-together yarn components, that devices for interrupting the operation of the devices for the winding-up are provided, which are controlled by devices for monitoring the yarn components with respect to breakage, and that devices are present for gripping the unbroken yarn component and holding it ready.
In a further development of preferred embodiments of the invention, the devices for the gripping and the holding-ready are constructed as a clamping device. In this construction, it must be provided that the actuating of the devices for the gripping and the holding-ready is coordinated with the stoppage of the partially wound spool, so that the remaining yarn component is not torn.
In another development of preferred embodiments of the invention, it is provided that the devices for the gripping and the holding-ready contain at least one suction nozzle. A suction nozzle of this type can take up the remaining yarn component in the form of a yarn loop which holds the yarn component only relatively lightly, so that it can still be withdrawn from the possibly still running-down partially wound spool.
As a rule, it will be provided that the continuous supply of the remaining yarn component is interrupted as soon as the partially wound spool has come to a stop. In order to avoid that too much fiber material is lost when one yarn component breaks, it is expediently provided to stop the partially wound spool as early as possible. This may take place by providing devices for lifting the partially wound spool off a driving device. In addition, in a further development of the invention, devices may be provided for braking the partially wound spool. These devices may, for example, be applied to the face of the partially wound spool or to the sleeve of the partially wound spool onto which the double yarn is wound. It is also contemplated to introduce a plate or a piece of sheet metal between the wind-up roller and the spool for a lifting and simultaneous braking of the partially wound spool.